Random access procedure for enhanced coverage support

ABSTRACT

Embodiments described herein relate generally to a communication between a user equipment (UE) and an evolved Node B (eNB) that are both running in Enhanced Coverage (EC) mode. The UE and eNB may communicate in a contention-based random access procedure having an EC level that may be used to determine the number of times an RA preamble may be sent, and one or more RA response opportunity windows that may be used to receive one or more RA responses. Other embodiments may be described and/or claimed.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/861,828, entitled “RANDOM ACCESS PROCEDURE FOR ENHANCED COVERAGESUPPORT,” filed Sep. 22, 2015, which claims priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 62/145,335 entitled“Random Access Procedure for Enhanced Coverage Support” and filed Apr.9, 2015, the entire disclosures of which are incorporated herein byreference.

FIELD

Embodiments of the present disclosure relate generally to the field ofwireless communications, and more particularly, to computer devicesoperable to implement a contention-based random access procedure.

BACKGROUND

The background description provided herein is for the purpose ofgenerally presenting the context of the disclosure. Work of thepresently named inventors, to the extent it is described in thisbackground section, as well as aspects of the description that may nototherwise qualify as prior art at the time of filing, are neitherexpressly nor impliedly admitted as prior art against the presentdisclosure. Unless otherwise indicated herein, the approaches describedin this section are not prior art to the claims in the presentdisclosure and are not admitted to be prior art by their inclusion inthis section.

Machine-type communication (MTC) technology may enable ubiquitouscomputing environments as progress moves towards the concept of the“Internet of Things” (IoT). Potential MTC-based applications includesmart metering, healthcare monitoring, remote security surveillance,intelligent transportation systems, individual item inventory control,and so forth. These services and applications may stimulate the designand development of a new type of MTC device that may be seamlesslyintegrated into current and future generation mobile broadband networks.

Existing mobile broadband networks are designed to optimize performancemainly for human-type communications. Therefore, existing networks maynot be adapted or optimized for MTC-related requirements. MTC-specificdesigns may be explored, for example, by the Third GenerationPartnership Project (3GPP). Future 3GPP specifications may supportdifferent network design, which may improve MTC.

For example, in 3GPP release 12 a new physical layer UE category,referred to as Category 0, was introduced into the E-UTRAspecifications. This UE category has lower capabilities, for example interms of peak data rate capability and in terms of transmission andreception performance due to support of only a single antenna, than theprevious lowest Category 1. One of the aims for introducing Category 0is to enable lower cost user equipment (UE) for MTC applications.

In 3GPP release 13 a new physical layer UE category (Category X) isbeing introduced having even lower capability and lower cost, comparedto Category 0 added in release 12. In addition, an Enhanced Coverage(EC) feature is being introduced to increase the link budget by up to 15decibels (dB). The EC feature will enable the E-UTRAN to communicatewith UEs that are located in challenging locations where currentlycoverage cannot be provided or is difficult to provide to UEs, forexample deep inside a building, in a basement, inside a pallet of goodsand the like. Category X and EC are targeted to UEs primarily used forMTC applications. Category X and EC may be independently implemented anda UE may support either one or both.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments of the disclosure are illustrated by way of example andnot by way of limitation in the figures of the accompanying drawings inwhich like references indicate similar elements. It should be noted thatreferences to “an” or “one” embodiment of the disclosure are notnecessarily to the same embodiment, and they may mean at least one. Itshould also be noted that references to an “example” are references tonon-limiting examples, unless otherwise stated.

FIG. 1 illustrates a communication message flow between an evolved NodeB (eNB) and a user equipment (UE) using EC mode, in accordance withvarious embodiments.

FIG. 2A illustrates a process for a contention-based random accessprocedure performed by a UE using EC functionality, in accordance withvarious embodiments.

FIG. 2B illustrates a process for contention-based random accessprocedure performed by a UE using EC functionality, in accordance withvarious embodiments.

FIGS. 3A, 3B, and 3C are diagrams illustrating frame structures that maybe used for implementing random access response (RAR) opportunitieswithin an EC RAR window that may be used by a UE and an eNB, inaccordance with various embodiments.

FIG. 4 is a diagram illustrating frame structures for implementing adifferent modification period for the system information (SI) addressedto a UE in EC mode, in accordance with various embodiments.

FIG. 5 is a block diagram illustrating a computing device adapted tooperate in a wireless communication network in EC mode, in accordancewith various embodiments.

FIG. 6 illustrates electronic device circuitry that may be eNBcircuitry, UE circuitry, or some other type of circuitry in accordancewith various embodiments.

FIG. 7 illustrates, for one embodiment, an example system comprisingradio frequency (RF) circuitry, baseband circuitry, applicationcircuitry, memory/storage, display, camera, sensor, and input/output(I/O) interface, coupled with each other at least as shown.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings, which form a part hereof wherein like numeralsdesignate like parts throughout, and in which is shown by way ofillustration embodiments that may be practiced. It is to be understoodthat other embodiments may be utilized and structural or logical changesmay be made without departing from the scope of the present disclosure.Therefore, the following detailed description is not to be taken in alimiting sense, and the scope of embodiments is defined by the appendedclaims and their equivalents.

Various operations may be described as multiple discrete actions oroperations in turn, in a manner that is most helpful in understandingthe claimed subject matter. However, the order of description should notbe construed as to imply that these operations are necessarily orderdependent. In particular, these operations may not be performed in theorder of presentation. Operations described may be performed in adifferent order than the described embodiment. Various additionaloperations may be performed and/or described operations may be omittedin additional embodiments.

For the purposes of the present disclosure, the phrases “A or B” and “Aand/or B” means (A), (B), or (A and B). For the purposes of the presentdisclosure, the phrase “A, B, and/or C” means (A), (B), (C), (A and B),(A and C), (B and C), or (A, B, and C).

The description may use the phrases “in an embodiment,” or “inembodiments,” which may each refer to one or more of the same ordifferent embodiments. Furthermore, the terms “comprising,” “including,”“having,” and the like, as used with respect to embodiments of thepresent disclosure, are synonymous.

As used herein, the terms “module” and/or “logic” may refer to, be partof, or include an Application Specific Integrated Circuit (ASIC), anelectronic circuit, a processor (shared, dedicated, or group), and/ormemory (shared, dedicated, or group) that execute one or more softwareor firmware programs, a combinational logic circuit, and/or othersuitable hardware components that provide the described functionality.

As used herein, the term “circuitry” may refer to, be part of, orinclude an ASIC, an electronic circuit, a processor (shared, dedicated,or group), and/or memory (shared, dedicated, or group) that execute oneor more software or firmware programs, a combinational logic circuit,and/or other suitable hardware components that provide the describedfunctionality. In some embodiments, circuitry may be implemented in, orfunctions associated with the circuitry may be implemented by, one ormore software or firmware modules.

In embodiments, the disclosure herein may refer to processes, apparatus,and/or techniques for enhancing machine-to-machine communication relatedto the random access procedure process between an evolved NodeB (eNB)and a user equipment (UE) running in EC mode. These embodiments mayinclude associating multiple levels with an EC mode, and for each levelidentifying a number of repetitions of messages sent between the UE andthe eNB, as well as different power levels that may be used by the UE toattempt communication with an eNB depending upon the EC mode level. Inaddition, embodiments may include adding additional random accessresponse (RAR) opportunity windows to receive and decode multiple RAR'sthat may be sent in response to multiple random access preambles. Also,embodiments may include support for a different modification period forthe SI messages addressed to release-13 LC UEs and release-13 EC UEs.

In embodiments, UEs using this solution may operate in reduced bandwidthregions, such as 1.4 MHz in release-13, or may operate in morenarrowband regions, such as 200 kHz. The eNB may also operate at highersystem bandwidth.

FIG. 1 illustrates a communication message flow between a UE and an eNBusing EC mode, in accordance with various embodiments. Diagram 100 mayinclude a UE 102 and wireless communication with an access node such aseNB 104. The UE 102 and the eNB 104 may be in communication to establisha radio resource control (RRC) connection using a contention-based RAprocedure in EC mode.

An EC random access (RA) preamble assignment 106 may be sent from theeNB 104 to the UE 102. In embodiments, the RA preamble assignment 106may include random access configuration information related to release13 LC (low cost) UEs and release 13 EC mode UEs and may be broadcastedthrough system information (SI), or may be pre-defined in the UE 102.Random access configuration information, in embodiments, may include anEC level to be used by the UE 102, a value indicating the number ofadditional repetitions of each EC mode message allowed for that EClevel, and/or one or more power levels to be used for repeatedcommunication attempts.

An EC RA preamble 108 may be sent from the UE 102 to the eNB 104. An ECRAR message 110 may be sent by the eNB 104 in response to the EC RApreamble 108, within an EC RAR window which, in embodiments, may bereceived in a plurality of contiguous subframes. The contents of the ECRA preamble 108 may determine the random access radio network temporaryidentifier (RA-RNTI) that the UE 102 may look for in EC RA response (ECRAR) message 110 subframes received from the eNB 104.

In embodiments, the eNB 104 may have flexibility regarding the locationwithin the EC RAR window the EC RAR message 110 is transmitted. Inembodiments, the UE 102 may search for a RA-RNTI on a physical downlinkcontrol channel (PDCCH). In embodiments, the PDCCH received by UE in ECmode may be different from legacy PDCCHs. For example, the legacy PDCCHmay be sent within the whole system bandwidth in the first OFDMA symbolsof a subframe. However, for EC mode, the PDCCH may be sent in reducedbandwidth region within the legacy PDCCH.

The EC RAR message 110 may include a random access preamble identifier(RAPID) and a temporary cell radio network temporary identifier(T-CRNTI).

An EC scheduled transmission 112 may be sent by the UE 102 to the eNB104. In embodiments, if the EC RAR message 110 is received in sub-framen, the UE 102 may send a scheduled data item via physical uplink sharedchannel (PUSCH) in subframe n+k, k≥6. The UE 102 may further applyHybrid Automatic Repeat Request (HARQ) with maxHARQ-Msg3Tx. The UE 102may also start a timer such as timer T300 for RRC connection request andmonitor for T-CRNTI on PDCCH. Finally, the UE 102 may startmac-ContentionResolutionTimer. In embodiments, themac-ContentionResolutionTimer may be restarted at each HARQretransmission.

An EC contention resolution message 114 may be sent by the eNB 104 tothe UE 102. In embodiments, the T-CRNTI is used in PDCCH and HARQ may beapplied for the associated PDSCH by eNB 104. In embodiments, the UE 102may send HARQ feedback only on PUCCH when it detects its own UE 102identity as provided in the EC scheduled transmission 112. Inembodiments, the EC contention resolution message 114 may be received byUE 102 while mac-ContentionResolutionTimer is running. If EC contentionresolution message 114 is received successfully, the UE 102 ContentionResolution Identity MAC CE may contain the UL common control channel(CCCH) service data unit (SDU) of the EC contention resolution message114.

In embodiments, advantages of the communications in EC mode describedabove may include a greater likelihood of an RRC connectionestablishment between a UE and eNB, particularly when the UE isimplemented as part of IoT. Advantages may also include providing agreater likelihood of an RRC connection establishment while using lesspower, for example by ramping up power used by the UE to the point wherethe RA procedure is able to establish an RRC connection, where the UEdoes not have to continuously operate a maximum power. In addition,through supporting repeated attempts for transmissions between the UEand the eNB during the RA procedure, the likelihood of an RRC connectionestablishment is greatly increased.

FIG. 2A illustrates a process for a contention-based random accessprocedure performed by a UE using EC functionality, in accordance withvarious embodiments. The process 200 describes various processesdescribed above in more detail. The process 200 may be performed by aUE, for example UE 102, used in EC mode operation in accordance withvarious embodiments. In some embodiments, the UE may include one or morenon-transitory computer-readable media having instructions, storedthereon, that when executed cause the UE to perform the process 200.

The process may start at block 202.

At block 204, the UE 102 may receive random access procedure (RACH)configuration information from an eNB 104. In embodiments, theconfiguration information may be received by the UE 102 from the EC RApreamble assignment message 106, for example when the UE 102 is in idlemode and capable of EC mode. The configuration information may bebroadcasted through SI by the eNB 104. In other embodiments, theconfiguration information may have been previously stored in the UE 102.

At block 206, the UE 102 may initialize RA related elements. Inembodiments, the UE may initialize related elements similar to legacy RAmechanisms. In embodiments, new RA related parameters for EC mode UEsmay be initialized. The RA related parameters may be, for example EClevel, initial power level, or number of times to repeat a message.

At block 208, the UE 102 may make a determination related to whethercriteria are met for the UE to start EC mode, or if a legacy RAprocedure may be started. In embodiments, the UE 102 may decide which RAprocedure mode may be used by information defined in specification,stored on the UE, and/or indicated to the UE through broadcast ordedicated messages. In examples, new rules, conditions, or criteria maybe defined. For example, a rule may be defined that a UE having one ormore unsuccessful completions under a legacy RA procedure may attempt touse EC RA procedure.

In other non-limiting examples, threshold values may be used to triggeror determine when a UE should use an EC RA procedure. These thresholdvalues could be defined based on some UE specific parameter, such asmeasured reference signal received power (RSRP), measured referencesignal received quality (RSRQ), preamble transmission counter value orphysical random access channel (PRACH) preamble transmission power.

In other non-limiting examples, the determination may be based on thepredefined category/capability specific information that is stored atthe UE 102. For example, UE Category X may be required to always use ECRA procedures, or alternatively UE Category X may be allowed to use ECRA procedure based on other criteria in addition to its category.

If the criteria are not met to start EC mode, then at block 210 the UE102 may use the legacy RA procedure. The process 200 may then end atblock 234.

Otherwise, if the criteria are met to start EC mode, then at block 212the UE 102 may use EC mode for the RA procedure and identify thestarting EC level. In embodiments, the UE 102 may identify the EC levelto use based on a stored value within the UE 102, or by receiving and/ordecoding EC level information sent by the eNB 104 in the EC RA preambleassignment 106. The EC level may be important for a variety of reasons.For example, the RA related configuration may need to be updated basedon the EC level. The maximum UL transmit power may be chosen directlywith any EC level, or RA preambles and/or configurations may be based onthe identified EC level. The EC level may also be associated with aspecific number of message repetitions that are available to the UE 102while attempting to communicate with the eNB. As a result, the RAprocedure may use, for example, a number of repeated messages, with eachsubsequent repeat using an increased power level, or power ramp-up, whenattempting to establish an RRC connection. Other aspects related to theRA message resource allocation information within the EC RA preambleassignment 106 may include details of frequency hopping, the group ofsequences that may be used for the preamble transmission if the UE is inEC mode, and/or if different EC levels are identified by their preamblesequences.

At block 214, the UE 102 may send an RA preamble and correspondingcopies of the RA preamble based on the identified EC level. Inembodiments, the RA preamble may be repeatedly sent for a number oftimes based on the identified EC level. In embodiments, the RA preamblegroup and/or subgroup, RA preamble time resource (PRACH subframes),frequency resources, and the like may depend on the identified EC level,as well as the subframes where the UE 102 sends the multiple copies ofthe EC RA preamble to allow the network to combine the multiple EC RApreamble copies. In embodiments, there may be a maximum of n preamblecopies sent, n depending on the identified EC level. In embodiments, theUE 102 may determine the RA-RNTI based on the identified EC level, RApreamble, and RA preamble time and frequency resource.

At block 216, the UE 102 may begin to receive and/or to combineresources to receive an EC RAR message 110. In embodiments, the resourcelocation of the EC RAR message 110 may be known by the UE afterdetermining release 13 RA-RNTI, through a release 13 enhanced physicaldownlink control channel (ePDCCH) addressed to a group of UEs thatattempt to access with same EC level or EC RA preamble 108, or through arelease 13 ePDCCH addressed to specific UE or based onpre-configured/pre-defined information that is pre-defined and/orbroadcasted in an SI message. In addition, the EC RAR message 110 couldbe a release 13 RAR different for that EC level or could be UE specificor a new kind of EC RAR message 110 that may carry the random accessresponse. This process might be done only once, or repeated severaltimes if a release 13 EC RAR-window concept is also defined and/orextended, as described below.

At block 218, the UE 102 may determine whether the EC RAR message 110addressed to the UE was successfully decoded within a window of time. Inembodiments, the window of time may be the EC window value. Inembodiments, the window of time may vary based on the EC level, forexample it may be proportional to the EC level identified or may bebased on the maximum number of preamble repetitions allowed for the EClevel.

If the EC RAR message 110 was successfully decoded within a window oftime, then at block 220 the process goes to block 252 of FIG. 2B.

Otherwise, if the EC RAR message 110 was not successfully decoded withina window of time, then at block 222 the transmission counter may beincremented by one. In embodiments, the EC RAR message 110 may not havebeen successfully decoded because it may not have been sent by the eNB,or may have been sent but may not have contained the RAPID that the UEincluded in the EC RA preamble 108.

At block 224, the UE 102 may determine if the transmission counter isequal to the maximum transmission count for the current EC level. If thetransmission counter is equal to the maximum transmission count for thecurrent EC level, then at block 230 the UE 102 may determine that the ECRA procedure has unsuccessfully completed. In embodiments, this mayoccur if the maximum number of attempts is reached for the highest EClevel. In embodiments, the UE may inform the RRC upper layers about theRA failure, and the upper layers may initiate the EC RA procedure againat a later time. Based on the previous RA failure, the RA procedure maybe initiated by changing the EC level, for example incrementing the EClevel, to a level more suitable for when the UE is deeper within theenhanced coverage region of the cell such as deep within a building. Atblock 232, the process 200 may end.

Otherwise, if the transmission counter is not equal to the maximumtransmission count for the current EC level, then at block 226 the UE102 may wait for the back-off time to expire for the EC level. Inembodiments, the UE may try to send the EC RA preamble 108 again. Forexample, this may be done after applying preamble power ramping ifspecified or configured for EC. In embodiments, a transmission countermay be used to place a limit on the maximum number of PRACH preambletransmission trials for the current EC level. In embodiments, atransmission counter may determine when the UE may switch to another EClevel, for example to a higher EC level which may allow for more messagerepetitions or a higher power level.

At block 228, the UE 102 may increment the transmission counter by 1,and the process 200 may proceed to block 212.

FIG. 2B illustrates a process 250 for contention-based random accessprocedure performed by a UE using EC functionality, in accordance withvarious embodiments. The process 250 may be performed by a UE (e.g., UE102) for EC mode operation in accordance with various embodiments. Insome embodiments, the UE may include one or more non-transitorycomputer-readable media having instructions, stored thereon, that whenexecuted cause the UE to perform the process 250.

At block 252, the process 250 may continue from block 220 of FIG. 2A.

At block 254, the UE 102 may wait until the end of the EC window. Inembodiments, the UE may wait until the end of the EC window before itstarts transmitting the EC Scheduled Transmission message 112. Inembodiments, for any particular EC level identified, as described forexample in block 212, that EC level may have an associated number ofrepetitions identifying the number of times the EC RAR message 110 hasbeen sent. If the UE is able to decode the EC RAR message 110 earlierthan the number of times the EC RAR message 110 has been sent, the UEmay wait for the amount of time it may take the last EC RAR message 110to be received. In embodiments, the UL allocation of the EC scheduledtransmission 112 may be scheduled only after the last repetition of theEC RAR message 110 is sent by the eNB.

At block 256, the UE 102 may send a scheduled transmission, for examplean RRC connection request, to the eNB.

At block 258 the UE 102 may, after an identified time, begin to receivethe contention resolution message.

At block 260, the UE 102 may determine if the contention resolutionmessage addressed to the UE has been successfully received. A processsimilar to the EC RA procedure, as described above, may be applied orextended if the RA procedure fails in contention resolution phase 114.In embodiments, this may occur if the EC scheduled transmission 112 wasnot correctly received at the eNB or if the EC scheduled transmission112 from the given UE collided with another EC scheduled transmission112 and only the other UE's EC scheduled transmission 112 was detected.For the latter case, the given UE may receive the EC contentionresolution message 114 from the eNB but may determine that it was notaddressed to that specific UE.

In other embodiments, a concept similar to legacymac-ContentionResolutionTimer may be applied if EC contention resolution114 is not received while using EC mode. In these embodiments, the valueof this timer may scale or may be updated based on how long the ECrepetitions of the scheduled transmission 112 are expected to take. Thismay occur when the EC scheduled transmission 112 was not correctlyreceived by the eNB or the eNB received and responded but the ECcontention resolution 114 was not received successfully at the UE.

If the UE 102 determines that the contention resolution message has beensuccessfully received, then at block 264 the process 250 may end.

If the UE 102 determines that the contention resolution message has notbeen successfully received, then the process may proceed to block 262which then may return the process to block 208 of FIG. 2A.

In embodiments, when the EC contention resolution 114 fails, the UE mayapply an analogous procedure to resend the RA preamble with incrementingor re-initializing the preamble transmission counter. For the option ofre-initialization of the preamble transmission counter, the UE mayrestart the RA process again as in the case of legacy operation.

In embodiments, if the network conditions may have changed since theprevious RA trial, the process may allow the UE to switch to legacyprocedure instead of EC procedure, or vice versa. Additionally, theupdated network conditions may tell the UE to start from different EClevel.

For the embodiments described herein, for simplicity, the use of thecontention-based RA procedure for EC mode by a UE in RRC_IDLE may beshown, for example initiating an RRC connection. However, thecontention-based RA procedure for EC mode may also be used by a UE inRRC_CONNECTED. In addition, for simplicity, legacy names may be used forthe new release 13 EC RA parameters and embodied procedures. However,this should not be restricted to these names, as some of the names mayrefer to same parameters as used in the legacy RA procedure or may alsorefer to completely new and different parameters that get defined tofulfil the same functionality explained herein.

For example, in embodiments the UE may select the RA resourcesdifferently depending on whether the UE uses the legacy RA procedure orthe EC RA procedure. In addition, for the EC RA procedure, differentvalues of the legacy RA parameters or even different or new parametersmay be defined for EC mode or for each EC level. For example, back-offtime, which may be a parameter involved in the RA procedure, may haveone or more different values per EC level or different parameters mightbe defined for each EC level. In another example, the PREAMBLE_TRANS_MAXvalue may be updated or a new parameter may be defined to trigger whenthe legacy RA procedure may pass to the EC RA procedure. Alternatively,power ramping for preamble transmission may not be considered when ECmode is used in RA procedure, as the UE may use maximum transmit powerin challenging locations with poor coverage. In embodiments, the newrelease 13 criteria or conditions may be defined in the specification ormay be broadcasted for the UE to know which parameters or values shouldbe used for EC RA procedure or for a specific EC RA level.

FIGS. 3A, 3B, and 3C are diagrams illustrating example frame structuresfor implementing RAR opportunities within an EC RAR window that may beused by a UE when receiving an EC RAR, in accordance with variousembodiments.

In FIG. 3A, diagram 300 shows one implementation of an EC RAR window 304within a sequence of frames 302. In embodiments, the EC RAR window 304may start k subframes after the EC RA preamble transmission 108 issupposed to finish. In embodiments, k may be defined to a value of 3,for example, to accommodate devices operating in accordance with legacylong term evolution (LTE) RA procedures, or it may be a greater value,for example, in order to account for increased processing requirementsfor the eNB to support a reduced bandwidth UEs and EC mode.

In embodiments, the EC RAR window 304 may contain one or more EC RARopportunities 306. The number of EC RAR opportunities 306 a, 306 b, 306c within the EC RAR window 304 may be defined in the specification ormay be broadcasted as part of the EC RA Preamble assignment 106. Inembodiments, the first EC RAR 306 a may start at the same sub-frame asthe EC RAR window 304. The length of the EC RAR opportunity 306 a mayvary. For example, the length may depend on the number of repetitionsrequired for the EC level, or on how many of the subframes in the EC RARopportunity 306 a carry an actual EC RAR message 110. In embodiments,this may be due to the EC RAR message 110 being repeated multiple timesdue to repeated transmissions permitted by the EC level. Diagram 300shows an example where all of the subframes in the EC RAR opportunities306 a, 306 b, 306 c carry an EC RAR message 110.

In embodiments, the first transmission of the EC RA preamble 106 for aspecific EC level may occur within multiple RA preamble sub frames 302a. In embodiments, a specific EC RA preamble 302 a 1 may be sent inspecific time and frequencies, (i.e. resources) for the eNB to know thatthe UE is using a certain EC level. In embodiments, the EC RA preamblemay also identify whether this UE is release 13 LC. In embodiments,subsequent transmissions of the EC RA preamble 302 a 2 may use the ECRACH process for a specific EC level. For example, the subsequenttransmissions of the EC RA preamble 302 a 2 may be in differentsubframes (not shown).

In embodiments, after one or more transmissions of the EC RA preamble302 a, the UE may wait k subframes before starting the EC RAR window304.

In embodiments, the RAR opportunities 306 may have the same number offrames as the EC RAR window. In some embodiments, within the EC RARwindow 304, there may be a first EC RAR opportunity 306 a. UE maycombine the EC RAR related resources of each sub-frame within the firstEC RAR opportunity 306 a so that the EC RAR message 110 may be decoded.In embodiments, the UE may then look for a RA-RNTI and, if the RA-RNTIis found, the UE may then look for the RAR message.

In embodiments, the second EC RAR opportunity 306 b of the EC RAR window306 may be identified. In embodiments, this may be in response tosubsequent transmissions of the EC RAR message 110, for example aresponse to one of the EC RA preamble 108 repetitions, where the numberof repetitions may be identified based on EC level.

In embodiments, UE 102 using a certain EC level may require x 310 and y308 EC total repetitions for the uplink and downlink directionsrespectively, where x 310 or y 308 may have the same or different valuesfor uplink and downlink. In these embodiments, the EC repetitions areconsecutive.

In embodiments, after the EC RAR message 110 has been successfullydecoded, for example using data received from the second EC RARopportunity 306 b, the UE may wait z 312 subframes before sending an ECscheduled transmission 112 in the UL in accordance with the allocatedgrant from the decoded EC RAR message 110. In this example, the other ECRAR opportunity 306 c may be ignored because the UE has alreadysuccessfully decoded the RAR message from the eNB.

In embodiments, EC RAR window 304 may be formed in a number of ways. Forexample, the EC RAR window 304 may be formed by EC RAR opportunities 306a, 306 b, 306 c of one specific EC level. In embodiments, UEs that maybe checking that EC RAR window would have the same EC level requirement.As a result, the network might have a different EC RAR window 304 regionfor each EC level, which may have different locations in time, frequencyand/or number of EC required repetitions.

In embodiments, EC RAR opportunities 306 a, 306 b, 306 c may differbased on different EC levels. In these embodiments, the network mayindicate or the 3GPP LTE specification may define which EC level maycorrespond to each EC RAR opportunity (not shown). In embodiments, allopportunities of the same EC level may be located consecutively or theymay be alternated.

In FIG. 3B diagram 325 shows an example of an EC RAR window where notall subframes in the EC RAR opportunities 306 a, 306 b, 306 c carry anEC RAR message 110. For example, UE 102 may be using an EC level thatmay require x 316 and y 314 EC total repetitions for each downlink anduplink direction respectively, where x 316 and y 314 may have the sameor different values. In this example, EC repetitions are not inconsecutive subframes.

In FIG. 3C, diagram 350 shows embodiments where the length of the EC RARopportunities 306 a, 306 b, 306 c may also vary if, in addition to theEC RAR message 110, an RA control indicator (EC RA-RNTI) is received.For example, in the second EC RAR opportunity window 318, the RA controlidentifier 318 a is prepended to the RAR message 318 b. In this example350, the EC repetitions are consecutive. In embodiments the RA controlidentifier 318 a area may be used for other RAR messaging.

The additional message added to the RAR opportunity window may be due torepetitions of the Physical Downlink Control Channel (PDCCH) for MTCthat may be based on release 13 enhanced physical downlink controlchannel (ePDCCH). The downlink control information (DCI) carried by thisPDCCH, with its cyclic redundancy check CRC scrambled with the ECRA-RNTI, may schedule the transmission of the RAR message usingcross-sub-frame scheduling.

In embodiments (not shown), some EC RA parameters, such as EC RApreamble, EC RAR window, and EC RAR opportunity, may be defineddifferently depending on the EC level, for example 5 decibels (dB) EC vs10 dB EC. Examples may include different starting times, differentallocation of frequency resources, or number of EC repetitions required.

Additionally, in embodiments, the number of EC repetitions for each RAmessage sent between the UE and eNB in EC mode may be the same or maydiffer for each message. In embodiments, the number of repetitions maydiffer, based on the number of repetitions of one or more of theprevious messages sent between the UE and eNB in EC mode. For example,the number of repetitions for the EC RAR message 110 may be a functionof the number of repetitions for EC RA preamble 108, with an adjustmentbased on the difference between the downlink and uplink timing. Inanother example, the number of repetitions for the EC scheduledtransmission 112 may be indicated in the EC RAR message 110 or may beotherwise specified.

FIG. 4 is a diagram illustrating frame structures for implementing adifferent modification period for the SI addressed to a UE in EC mode,in accordance with various embodiments.

Diagram 400 shows, in embodiments, an rSIB1 which may be used forrelease 13 low complexity and delay tolerant UEs, such as release 13 LCUE and release 13 UEs capable of using EC mode. For this rSIB1 thatcontains cell specific configuration information may be changed same asfor legacy SIBs at instances other than that of the N+k*M frame 404. Inembodiments, implementing an rSIB1 may have the advantage of lesseningthe impact and restrictions on legacy network behavior.

In embodiments, a first rSIB, rSIB1 406, may have the same modificationperiod as legacy SIBs and the rSIB1 406 also may be updated at the N+Mframe 408. In embodiments, other rSIBs 410 which do not contain cellspecific configuration information may be changed less frequently, forexample less often with longer modification periods. In embodiments,rSIB1 406 and other SIBs 412 may have the same modification period andmay be updated at the end of the N+k*M frame 404.

FIG. 5 illustrates a simplified block diagram of UE 102 of FIG. 1 inaccordance with various embodiments of the disclosure. As shown in FIG.5, UE 102 includes a processor 510, radio frequency (RF) circuitry 540and a memory 520. The processor 510 may include one or more single-coreor multi-core processors, and may include any combination ofgeneral-purpose processors and dedicated processors (e.g. graphicsprocessors, application processors, baseband processors, etc.). Inaccordance with various embodiments, the processor 510 (and inparticular, a baseband chipset of the processor 510) may includeconfiguration logic. The configuration logic may be operable to identifyan initial EC level that is to be used during a contention-based RAprocedure, the EC level having at least an associated power level,window of time, and number of send attempts. The configuration logic maybe operable to send a first message to a radio access network (RAN)based on the identified EC level. The configuration logic may beoperable to determine whether a second message from the RAN in responseto the first message is received within the window of time. Theconfiguration logic may be operable to, if the second message isreceived from the eNB within the window of time, decode the receivedsecond message. The configuration logic may be operable to, if thesecond message is not received from the eNB within the window of time,re-send the first message to the RAN and track a number of times thefirst message has been sent using a transmission counter having anumerical value; and output an indication that the EC RA procedure didnot complete successfully based on determination of a whether the secondmessage is received within a window of time and a comparison of thetransmission counter to a transmission threshold value.

The RF circuitry 540 may be coupled to the processor 510, for examplevia a bus 530, and may be used to transmit or receive data.

The memory 520 may include one or more non-transitory, computer-readablemedia having instructions stored thereon, and the instructions whenexecuted by the processor 510 may cause UE 102 to perform the operationsdescribed above in connection with the processor 510. However, this isonly illustrative rather than limiting; those of ordinary skill in theart will appreciate alternative implementations in software, hardware,firmware, or any combination thereof.

FIG. 6 illustrates electronic device circuitry 602 that may be eNBcircuitry, UE circuitry, or some other type of circuitry in accordancewith various embodiments. In embodiments, the electronic devicecircuitry 602 may be, or may be incorporated into or otherwise a partof, an eNB, a UE, or some other type of electronic device. Inembodiments, the electronic device circuitry 602 may include radiotransmit circuitry and receive circuitry coupled to control circuitry606. In embodiments, the transmit 604 and/or receive circuitry 608 maybe elements or modules of transceiver circuitry, as shown. Theelectronic device circuitry 602 may be coupled with one or moreplurality of antenna elements of one or more antennas 610. Theelectronic device circuitry and/or the components of the electronicdevice circuitry may be configured to perform operations similar tothose described elsewhere in this disclosure.

In embodiments where the electronic device circuitry 602 is a UE or ispart of or otherwise incorporated into a UE, the UE may be capable ofoperation in accordance with EC mode. The control circuitry 606 may beto identify the EC mode. The control circuitry 606 may be further tooperate in accordance with the EC mode. The transmit 604 and/or receivecircuitry 608 may be to send and/or receive one or more signals ortransmissions in accordance with the EC mode.

In embodiments where the electronic device circuitry 602 is an eNB or ispart of or otherwise incorporated into an eNB the electronic device maybe capable of operation of different modification periods fortransmission and update of SI. The control circuitry 606 may be toidentify a modification period from a plurality of modification periods.The transmit circuitry 604 may be to transmit a transmission and/orupdate of SI in accordance with the identified modification period.

As used herein, the term “circuitry” may refer to, be part of, orinclude an Application Specific Integrated Circuit (ASIC), an electroniccircuit, a processor (shared, dedicated, or group), and/or memory(shared, dedicated, or group) that execute one or more software orfirmware programs, a combinational logic circuit, and/or other suitablehardware components that provide the described functionality. In someembodiments, the electronic device circuitry 602 may be implemented in,or functions associated with the circuitry may be implemented by, one ormore software or firmware modules.

Embodiments described herein may be implemented into a system using anysuitably configured hardware and/or software. FIG. 7 illustrates, forone embodiment, an example system 702 comprising RF circuitry 704,baseband circuitry 706, application circuitry 708, memory/storage 710,display 712, camera 714, sensor 716, and input/output (I/O) interface718, coupled with each other at least as shown.

The application circuitry 708 may include circuitry such as, but notlimited to, one or more single-core or multi-core processors. Theprocessor(s) may include any combination of general-purpose processorsand dedicated processors (e.g., graphics processors, applicationprocessors, etc.). The processors may be coupled with memory/storage andconfigured to execute instructions stored in the memory/storage toenable various applications and/or operating systems running on thesystem.

The baseband circuitry 706 may include circuitry such as, but notlimited to, one or more single-core or multi-core processors. Theprocessor(s) may include a baseband processor. The baseband circuitry706 may handle various radio control functions that enablescommunication with one or more radio networks via the RF circuitry. Theradio control functions may include, but are not limited to, signalmodulation, encoding, decoding, radio frequency shifting, etc. In someembodiments, the baseband circuitry 706 may provide for communicationcompatible with one or more radio technologies. For example, in someembodiments, the baseband circuitry 706 may support communication withan evolved universal terrestrial radio access network (EUTRAN) and/orother wireless metropolitan area networks (WMAN), a wireless local areanetwork (WLAN), a wireless personal area network (WPAN). Embodiments inwhich the baseband circuitry is configured to support radiocommunications of more than one wireless protocol may be referred to asmulti-mode baseband circuitry.

In various embodiments, baseband circuitry 706 may include circuitry tooperate with signals that are not strictly considered as being in abaseband frequency. For example, in some embodiments, baseband circuitry706 may include circuitry to operate with signals having an intermediatefrequency, which is between a baseband frequency and a radio frequency.

RF circuitry 704 may enable communication with wireless networks usingmodulated electromagnetic radiation through a non-solid medium. Invarious embodiments, the RF circuitry 704 may include switches, filters,amplifiers, etc. to facilitate the communication with the wirelessnetwork.

In various embodiments, RF circuitry 704 may include circuitry tooperate with signals that are not strictly considered as being in aradio frequency. For example, in some embodiments, RF circuitry 704 mayinclude circuitry to operate with signals having an intermediatefrequency, which is between a baseband frequency and a radio frequency.

In various embodiments, transmit circuitry 604, control circuitry 606,and/or receive circuitry 608 discussed or described herein may beembodied in whole or in part in one or more of the RF circuitry, thebaseband circuitry, and/or the application circuitry. As used herein,the term “circuitry” may refer to, be part of, or include an ASIC, anelectronic circuit, a processor (shared, dedicated, or group), and/ormemory (shared, dedicated, or group) that execute one or more softwareor firmware programs, a combinational logic circuit, and/or othersuitable hardware components that provide the described functionality.In some embodiments, the electronic device circuitry may be implementedin, or functions associated with the circuitry may be implemented by,one or more software or firmware modules.

In some embodiments, some or all of the constituent components of thebaseband circuitry, the application circuitry, and/or the memory/storagemay be implemented together on a system on a chip (SOC).

Memory/storage 710 may be used to load and store data and/orinstructions, for example, for system. Memory/storage 710 for oneembodiment may include any combination of suitable volatile memory(e.g., dynamic random access memory (DRAM)) and/or non-volatile memory(e.g., Flash memory).

In various embodiments, the I/O interface 718 may include one or moreuser interfaces designed to enable user interaction with the systemand/or peripheral component interfaces designed to enable peripheralcomponent interaction with the system. User interfaces may include, butare not limited to a physical keyboard or keypad, a touchpad, a speaker,a microphone, etc. Peripheral component interfaces may include, but arenot limited to, a non-volatile memory port, a universal serial bus (USB)port, an audio jack, and a power supply interface.

In various embodiments sensor 716 may include one or more sensingdevices to determine environmental conditions and/or locationinformation related to the system. In some embodiments, the sensors 716may include, but are not limited to, a gyro sensor, an accelerometer, aproximity sensor, an ambient light sensor, and a positioning unit. Thepositioning unit may also be part of, or interact with, the basebandcircuitry 706 a and/or RF circuitry 704 to communicate with componentsof a positioning network, e.g., a global positioning system (GPS)satellite.

In various embodiments, the display 712 may include a liquid crystaldisplay, a touch screen display, and the like.

In various embodiments, the system 702 may be a mobile computing devicesuch as, but not limited to, a laptop computing device, a tabletcomputing device, a netbook, an ultrabook, a smartphone, etc. In variousembodiments, system may have more or less components, and/or differentarchitectures.

In various embodiments, the system 702 may be a mobile computing devicesuch as, but not limited to, a laptop computing device, a tabletcomputing device, a netbook, an ultrabook, a smartphone, etc. In variousembodiments, system may have more or less components, and/or differentarchitectures. For example, in some embodiments the RF circuitry 704and/or the baseband circuitry 706 may be embodied in communicationcircuitry (not shown). The communication circuitry may include circuitrysuch as, but not limited to, one or more single-core or multi-coreprocessors and logic circuits to provide signal processing techniques,for example, encoding, modulation, filtering, converting, amplifying,etc., suitable to the appropriate communication interface over whichcommunications will take place. The communication circuitry maycommunicate over wireline, optical, or wireless communication mediums.In embodiments in which the system is configured for wirelesscommunication, the communication circuitry may include the RF circuitryand/or baseband circuitry to provide for communication compatible withone or more radio technologies. For example, in some embodiments, thecommunication circuitry may support communication with an evolveduniversal terrestrial radio access network (EUTRAN) and/or otherwireless metropolitan area networks (WMAN), a wireless local areanetwork (WLAN), a wireless personal area network (WPAN).

Embodiments of the technology herein may be described as related to the3GPP long term evolution (LTE) or LTE-advanced (LTE-A) standards. Forexample, terms or entities such as eNB, mobility management entity(MME), UE, etc. may be used that may be viewed as LTE-related terms orentities. However, in other embodiments the technology may be used in orrelated to other wireless technologies such as the Institute ofElectrical and Electronic Engineers (IEEE) 802.16 wireless technology(WiMax), IEEE 802.11 wireless technology (WiFi), various other wirelesstechnologies such as global system for mobile communications (GSM),enhanced data rates for GSM evolution (EDGE), GSM EDGE radio accessnetwork (GERAN), universal mobile telecommunications system (UMTS), UMTSterrestrial radio access network (UTRAN), or other 2G, 3G, 4G, 5G, etc.technologies either already developed or to be developed. In thoseembodiments, where LTE-related terms such as eNB, MME, UE, etc. areused, one or more entities or components may be used that may beconsidered to be equivalent or approximately equivalent to one or moreof the LTE-based terms or entities.

Some non-limiting examples may include the following:

Example 1 may include a user equipment (UE) capable of operation inaccordance with enhanced coverage (EC) mode, the UE comprising: controlcircuitry to: identify the EC mode; and operate in accordance with theEC mode; and transmit and/or receive circuitry coupled with the controlcircuitry, the transmit and/or receive circuitry to send and/or receiveone or more signals or transmissions in accordance with the EC mode.

Example 2 may include the subject matter of Example 1 or some otherexample herein, wherein the control circuitry, transmit circuitry,and/or receive circuitry are further to transmit, receive, and/orcombine multiple repetitions of a message to enhance its coverage.

Example 3 may include the subject matter of Example 1 or some otherexample herein, wherein the UE is to operate on normal system bandwidth(BW) as well as reduced BW within the whole system BW.

Example 4 may include the subject matter of Example 1 or some otherexample herein, wherein the UE is to operate with delay tolerant machinetype communications (MTC).

Example 5 may include the subject matter of Example 1 or some otherexample herein, wherein the UE may trigger the usage of one or moredifferent EC levels based on a desired coverage enhancement.

Example 6 may include the subject matter of Example 1 or some otherexample herein, wherein the UE may use EC mode for a random access (RA)procedure.

Example 7 may include the subject matter of Example 6 or some otherexample herein, wherein the UE may use EC mode for contention-based RAprocedure.

Example 8 may include the subject matter of Example 6 or some otherexample herein, wherein the trigger events to use EC mode for RAprocedure may be related to or based on a desired EC level.

Example 9 may include the subject matter of Example 6 or some otherexample herein, wherein the trigger to use EC mode for RA procedure maybe based on or related to a failure of a normal (legacy) RA procedure.

Example 10 may include the subject matter of Example 6 or some otherexample herein, wherein the trigger to use EC mode for RA procedure maybe related to or based on reaching a certain threshold, criteria orcondition such as, maximum number of preamble transmissions, maximumpreamble transmission power or thresholds for measured reference signalpower/quality (RSRP/RSRQ).

Example 11 may include the subject matter of Example 6 or some otherexample herein, wherein the UE may use different RA configurationinformation depending on the EC level.

Example 12 may include the subject matter of Example 6 or some otherexample herein, wherein the control circuitry may trigger the usage ofEC mode due to failure of the reception of RA message 2 (RAR).

Example 13 may include the subject matter of Example 6 or some otherexample herein, wherein the UE may trigger the usage of EC mode due tofailure of the reception of RA message 4 (such as, RRC ConnectionSetup).

Example 14 may include the subject matter of Example 6 or some otherexample herein, wherein the UE may use enhanced coverage random accessresponse (EC RAR) window to monitor the RA message 2 (RAR) sent inresponse to RA message 1 (RA preamble).

Example 15 may include the subject matter of Example 14 or some otherexample herein, wherein EC RAR opportunities may be defined within theEC RAR window.

Example 16 may include the subject matter of Example 14 or some otherexample herein, wherein the repetitions of the RA message 2 may bescheduled with a known pattern i.e. predefined or preconfigured withinthe EC RAR opportunities.

Example 17 may include the subject matter of Example 14 or some otherexample herein, wherein repetitions of the RA message 2 may not beincluded in all subframes within the EC RAR opportunities.

Example 18 may include the subject matter of Example 14 or some otherexample herein, wherein within the EC RAR opportunities controlinformation carrying the EC RA control identifier (i.e. EC RA radionetwork temporary identifier (RNTI)) as well as the EC RA message 2(RAR) is transmitted.

Example 19 may include the subject matter of Example 18 or some otherexample herein, wherein the UE may not need to receive EC RA message 2if no control information is received that includes the EC RA RNTI thatis addressed to the UE.

Example 20 may include an evolved NodeB (eNB) capable of operation ofdifferent modification periods for transmission and update of systeminformation (SI), the eNB comprising: control circuitry to identify amodification period from a plurality of modification periods; andtransmit circuitry to transmit a transmission and/or update of SI inaccordance with the identified modification period.

Example 21 may include the subject matter of Example 20 or some otherexample herein, wherein the eNB may be capable to operate a cell innormal mode and in EC mode.

Example 22 may include the subject matter of Example 20 or some otherexample herein, wherein the eNB may define different modificationperiods for transmission and update of system information specific tonormal mode and EC mode.

Example 23 may include the subject matter of Example 20 or some otherexample herein, wherein the eNB may define the modification periods forSI parameters specific to the cell configuration with same value asnormal (legacy) UEs.

Example 24 may include a method comprising determining by the UE ofExamples 1-19, or of some other example herein, to choose between thelegacy RA proc. and EC RA proc. based on certain thresholds, criteria,configurations and/or requirements.

Example 25 may include the subject matter of Example 24 or some otherexample herein, wherein the thresholds, criteria, configurationsand/requirements are either preconfigured in the UE or signaled to theUE by the network using unicast and/or broadcast messages.

Example 26 may include the subject matter of Example 24, or of someother example herein, comprising repetition of RA message 1 (preamble)to support UEs requiring EC.

Example 27 may include the subject matter of Example 26 or some otherexample herein, further comprising of corresponding repetitions of thesubsequent RA responses and messages to support the UEs requiring EC.

Example 28 may include a method for the eNB in Examples 20-23 or someother example herein, notifying the UEs of Examples 1-19 of the certainthresholds, criteria, configurations and/or requirements for the EC UEsusing dedicated, unicast or broadcast messaging.

Example 29 may include an apparatus comprising means to perform one ormore elements of a method described in or related to any of examples24-28, or any other example, method or process described herein.

Example 30 may include one or more non-transitory computer-readablemedia comprising instructions to cause an electronic device, uponexecution of the instructions by one or more processors of theelectronic device, to perform one or more elements of a method describedin or related to any of examples 24-28, or any other example, method orprocess described herein.

Example 31 may include an apparatus comprising control circuitry,transmit circuitry, and/or receive circuitry to perform one or moreelements of a method described in or related to any of examples 24-28,or any other example, method or process described herein.

Example 32 may include a method of communicating in a wireless networkas shown and described herein.

Example 33 may include a system for providing wireless communication asshown and described herein.

Example 34 may include a device for providing wireless communication asshown and described herein.

Example 35 is an apparatus to be employed in a user equipment, UE, theapparatus comprising: one or more processors; a memory coupled to theone or more processors having instructions thereon that when executedcause the processors to: identify an initial enhanced coverage, EC,level that is to be used in a radio cell during a contention-basedrandom access, RA, procedure, the EC level having at least an associatedpower level, window of time, and number of send attempts; send a firstmessage to a radio access network, RAN, based on the identified EClevel; determine whether a second message from the RAN in response tothe first message is received within the window of time; if the secondmessage is received from the eNB within the window of time, decode thereceived second message; and if the second message is not received fromthe eNB within the window of time: re-send the first message to the RAN.

Example 36 may include the subject matter of Example 35 or some otherexample herein, wherein the RAN includes at least one enhanced NodeB,eNB.

Example 37 may include the subject matter of Example 35 or some otherexample herein, wherein re-send the first message to the RAN furthercomprises: track a number of times the first message has been sent usinga transmission counter having a numerical value; and output anindication that the RA EC procedure did not complete successfully basedon determination of a whether the second message is received within awindow of time and a comparison of the transmission counter to atransmission threshold value.

Example 38 may include the subject matter of Example 35 or some otherexample herein, wherein the first message is a random access, RA,preamble and the second message is a random access response, RAR.

Example 39 may include the subject matter of Example 35 or some otherexample herein, wherein an initial EC level is configured in the UE oris received in a system information block, SIB.

Example 40 may include the subject matter of Example 39 or some otherexample herein, wherein the SIB is received in a higher bandwidth or ina reduced bandwidth.

Example 41 may include the subject matter of Example 35 or some otherexample herein, wherein the power level at which the first message issent is based on one or more of: the value of the transmission counter,or the value of the EC level.

Example 42 may include the subject matter of Example 35 or some otherexample herein, wherein re-send the first message further includes powerramping.

Example 43 may include the subject matter of Example 42 or some otherexample herein, wherein the power ramping includes increasing the powerto a maximum power level associated with the EC level.

Example 44 may include the subject matter of Example 35 or some otherexample herein, wherein the window of time is dependent at least on anumber of EC RAR opportunities defined within an EC RAR window and/orthe number of send attempts for the EC level.

Example 45 may include the subject matter of Example 35 or some otherexample herein, wherein re-send the first message to the RAN furthercomprises: include a delay time before re-sending the first message, thedelay being one of a function of at least the EC level.

Example 46 may include the subject matter of any one of Examples 35-45or some other example herein, wherein the UE may be capable to operatein a normal coverage mode and in EC mode.

Example 47 is an apparatus to be employed in an evolved NodeB, eNB, theapparatus comprising: one or more processors; a memory coupled to theone or more processors having instructions thereon that when executedcause the processors to: determine enhanced coverage, EC, levels to beused in a radio cell during a contention-based random access, RA,procedure, send, in a system information block, SIB, to a userequipment, UE, located in the radio cell, an indication of thedetermined EC levels; receive an RA preamble from a UE, responsive tothe RA preamble, transmit a random access response, RAR, message.

Example 48 may include the subject matter of Example 47 or some otherexample herein, wherein send in a SIB an indication of the determined EClevels further includes send in a reduced bandwidth of 1.4 megahertz or200 kilohertz.

Example 49 may include the subject matter of Example 47 or some otherexample herein, wherein the eNB may be to operate a radio cell in normalcoverage mode and in EC mode.

Example 50 is an apparatus to be employed in a user equipment, UE, theapparatus comprising: logic circuitry to identify an enhanced coverage,EC level; transmit circuitry to send to a radio access network, RAN, arandom access, RA, preamble based on the identified EC level; logiccircuitry to identify an EC random access response, RAR, window regionhaving a plurality of subframes.

Example 51 may include the subject matter of Example 50 or some otherexample herein, further comprising: logic circuitry to identify an ECrandom access response, RAR, window region having a plurality ofsubframes, the EC RAR window region including one or more EC RARopportunities, each being a contiguous group of subframes, the first ECRAR opportunity beginning at the same sub-frame as the beginning of theRAR window region and beginning K subframes after the RA preamble wassent.

Example 52 may include the subject matter of Example 51 or some otherexample herein, further comprising receive circuitry to: receive, fromthe RAN, a candidate RAR in the first EC RAR opportunity; until acandidate RAR is able to be decoded, receive, from the RAN, a candidateRAR from an EC RAR opportunity; and if a candidate RAR is able to bedecoded, send, to the RAN, an RRC connection request.

Example 53 may include the subject matter of Example 50 or some otherexample herein, wherein the EC RAR window region is dependent on avalue: defined in the specification, broadcast as a part of the SImessage, associated with the EC level, or associated with the number ofthe subframes in EC RAR opportunities that contain an RAR message.

Example 54 is an evolved NodeB, eNB, comprising: control circuitry toidentify a system information, SI, modification period associated with aradio cell configuration from a plurality of SI modification periodswhen in reduced bandwidth mode; and transmit circuitry coupled with thecontrol circuitry, the transmit circuitry to transmit an SI message inaccordance with the identified modification period.

Example 55 may include the subject matter of Example 54 or some otherexample herein, wherein the control circuitry and transmit circuitry areto operate in normal coverage mode and/or in EC mode.

Example 56 may include the subject matter of Example 54 or some otherexample herein, wherein the control circuitry further defines themodification periods for SI parameters associated with the radio cellconfiguration with a same value as a normal coverage user equipment, UE.

Example 57 is one or more non-transitory computer-readable mediacomprising instructions that cause a user equipment, UE, in response toexecution of the instructions by the computing device, to: identify aninitial enhanced coverage, EC, level that is to be used in a radio cellduring a contention-based random access, RA, procedure, the EC levelhaving at least an associated power level, window of time, and number ofsend attempts; send a first message to a radio access network, RAN,based on the identified EC level; determine whether a second messagefrom the RAN in response to the first message is received within thewindow of time; if the second message is received from the eNB withinthe window of time, decode the received second message; and if thesecond message is not received from the eNB within the window of time,re-send the first message to the RAN.

Example 58 may include the subject matter of Example 57 or some otherexample herein, wherein the RAN includes at least one enhanced NodeB,eNB.

Example 59 may include the subject matter or Example 57 or some otherexample herein, wherein re-send the first message to the RAN furthercomprises: track a number of times the first message has been sent usinga transmission counter having a numerical value; and output anindication that the RA EC procedure did not complete successfully basedon determination of whether the second message is received within awindow of time and a comparison of the transmission counter to atransmission threshold value.

Example 60 may include the subject matter of Example 57 or some otherexample herein, wherein the first message is a random access, RA,preamble and the second message is a random access response, RAR.

Example 61 may include the subject matter of Example 57 or some otherexample herein, wherein an initial EC level is configured in the UE oris received in a system information block, SIB.

Example 62 may include the subject matter of Example 61 or some otherexample herein, wherein the SIB is received in a higher bandwidth or ina reduced bandwidth.

Example 63 may include the subject matter of Example 57 or some otherexample herein, wherein the power level at which the first message issent is based on one or more of: the value of the transmission counter,or the value of the EC level.

Example 64 may include the subject matter of Example 57 or some otherexample herein, wherein re-send the first message further includes powerramping.

Example 65 may include the subject matter of Example 64 or some otherexample herein, wherein the power ramping includes increasing the powerto a maximum power level associated with the EC level.

Example 66 may include the subject matter of Example 57 or some otherexample herein, wherein the window of time is dependent at least on anumber of EC RAR opportunities defined within an EC RAR window and/orthe number of send attempts for the EC level.

Example 67 may include the subject matter of Example 57 or some otherexample herein, wherein re-send the first message to the RAN furthercomprises: include a delay time before re-sending the first message, thedelay being one of a function of at least the EC level.

Example 68 may include the subject matter of any one of Examples 57-67or some other example herein, wherein the UE may be capable to operatein a normal coverage mode and in EC mode.

Example 69 is one or more non-transitory computer-readable mediacomprising instructions that cause an enhanced enodeB, eNB, in responseto execution of the instructions by the computing device, to: determineenhanced coverage, EC, levels to be used in a radio cell during acontention-based random access, RA, procedure, send, in a systeminformation block, SIB, to a user equipment, UE, located in the radiocell, an indication of the determined EC levels; receive an RA preamblefrom a UE, responsive to the RA preamble, transmit a random accessresponse, RAR.

Example 70 may include the subject matter of Example 69 or some otherexample herein, wherein send in a SIB an indication of the determined EClevels further includes send in a higher bandwidth or in a reducedbandwidth.

Example 71 may include the subject matter of Example 69 or some otherexample herein, wherein the eNB may be to operate a radio cell in normalcoverage mode and in EC mode.

Some portions of the preceding detailed description have been presentedin terms of algorithms and symbolic representations of operations ondata bits within a computer memory. These algorithmic descriptions andrepresentations are the ways used by those skilled in the dataprocessing arts to most effectively convey the substance of their workto others skilled in the arts. An algorithm is here, and generally,conceived to be a self-consistent sequence of operations leading to adesired result. The operations are those requiring physicalmanipulations of physical quantities.

It should be borne in mind, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities. Unlessspecifically stated otherwise as apparent from the above discussion, itis appreciated that throughout the description, discussions utilizingterms such as those set forth in the claims below refer to the actionand processes of a computer system, or similar electronic computingdevice, that manipulates and transforms data represented as physical(electronic) quantities within the computer system's registers andmemories into other data similarly represented as physical quantitieswithin the computer system memories or registers or other suchinformation storage, transmission, or display devices.

Embodiments of the disclosure also relate to an apparatus for performingthe operations herein. Such a computer program is stored in anon-transitory computer-readable medium. A machine-readable mediumincludes any mechanism for storing information in a form readable by amachine (e.g., a computer). For example, a machine-readable (e.g.,computer-readable) medium includes a machine- (e.g., a computer-)readable storage medium (e.g., read only memory (ROM), random accessmemory (RAM), magnetic disk storage media, optical storage media, flashmemory devices).

The processes or methods depicted in the preceding figures can beperformed by processing logic that comprises hardware (e.g., circuitry,dedicated logic, etc.), software (e.g., embodied on a non-transitorycomputer-readable medium), or a combination of both. Although theprocesses or methods are described above in terms of some sequentialoperations, it should be appreciated that some of the operationsdescribed can be performed in a different order. Moreover, someoperations can be performed in parallel rather than sequentially.

Embodiments of the present disclosure are not described with referenceto any particular programming language. It will be appreciated that avariety of programming languages can be used to implement the teachingsof embodiments of the disclosure as described herein. In the foregoingSpecification, embodiments of the disclosure have been described withreference to specific exemplary embodiments thereof. It will be evidentthat various modifications can be made thereto without departing fromthe broader spirit and scope of the disclosure as set forth in thefollowing claims. The Specification and drawings are, accordingly, to beregarded in an illustrative sense rather than a restrictive sense.

1. An evolved NodeB, eNB, comprising: control circuitry to identify asystem information, SI, modification period associated with a radio cellconfiguration from a plurality of SI modification periods when inreduced bandwidth mode; and transmit circuitry coupled with the controlcircuitry, the transmit circuitry to transmit an SI message inaccordance with the identified modification period.
 2. The apparatus ofclaim 1, wherein the control circuitry and transmit circuitry are tooperate in normal coverage mode and/or in EC mode.
 3. The apparatus ofclaim 1, wherein the control circuitry further defines the modificationperiods for SI parameters associated with the radio cell configurationwith a same value as a normal coverage user equipment, UE.